Pipe bending machine



Nov. 16, 1943. w M 2,334,661

PIPE BENDING MACHINE Filed Feb. 20, 1942 2 Sheets-Sheet 1 R. M. WEIMER PIPE BENDING MACHINE 2' Sheets-Shet 2 Filed Feb. 20, 1942 Nov. 16, 1943.

V Patented Nov. 16, 1943 2,334,661 PIfiE BEND ING MACHINE? Russell M. Weimer, Pittsburgh, -Pa., assignor to i Provident Trust Company, Pittsburgh, Pa., '11

corporation it-Pennsylvania i Application February 20, 1942, aar No. 431,624 8 Claims. (01. 153-4 )v This invention is an improvement in the art of bending pipe or tubing, particularly conduits of thin wall type, andin machines therefor. In such operations it is essential that the pipe or tube, of whatever crosssection be effectively, re

inforced or braced internally, but-also bent or curved by a progressive deflecting treatment whereby to effect and maintain continuous uninterrupted smoothness of all of its surfaces, both exterior and interior. In the machine inheld in position by aconforming socket and welding, or otherwise as preferred. It thus provides a short flat bearing for the end of, the blank against which it is temporarily 'clampedfas' by temperscreW lS in bearing bracket I4 firmly att'ached to table 2, supplemented ifdeSiredbyb volved Iutilize a curved edge stationary resisting former or die, around which the pipe or. tube is bent by an outer straight channelled partly-embracing bar member, actuated by an annularly moving roller. The invention is adapted to efiect bending of the tubular blank toany extent less than a complete circle, but substantially so. 7

One preferred embodiment of the machine is illustrated in the accompanying drawings, in

which: Fig. 1 is a plan view, partly broken away, showing the working elements at their initial position; g g

Fig. 2 is a View in elevation, partly in section on the line 11-11 of Fig. 1; V

Fig. 3 is a sectional detail plan view showing the terminal of the blank connected with the re-v sistingformer and engaged by the inner en the embracing bar member;

Fig. 4 is a plan view of the bent blank; Fig. 5 is a perspective detail View showingco operating relation between the blank and the bending bar; i

Fig. 6 is a fullsize cross section of a square blank and internal mandrel filling; 1

Fig. 7 is a similar view showing a modification thereof; I

Fig. 8 is a partial sectional view as in Fig. 2, showing the-wiping roller bearing-directly against the channelled bar member.

Referring to Figs. 1 and 2, a supporting civ vcular table 2 is rigidly mounted upon a cylindrical post 3 havinga base} and supporting floor connecting braces 5 terminating in a post-surrounding frame "supporting bearing 6. a M

Fixedly secured upon table 2 in any suitable manner, as by bolts 1, is the annular die wheel 8 having the shallow edge groove 9 for interfitting reception of one side portion of the squared blank A, of Figs; 6 and 7. Die wheel 8 is provided with an inserted block iii havingan outer flat face H between upper and lower flange projections 12 forming a channeled tangential extension ofthe peripheral groove 9. 1

. Block I is preferably of hard metal, firmly shimflor Wedge l 3a. 7 I 'For the purpose of wiping the blank progressively'around thean'nular grooved edge of wheel 8, mjmgm curve formation therewith,ls provided an elongated straig t rigid bar I having a blank? engaging groove .itfofsuficient depth to closely embrace the outer major portion of the blank.

' Bar 15. is of sufficient length to correspond at least to the entire annular length of the grooved edge of die wheel 8, and is initially located with its inner endclosely adjacent to block 10, as in Figs-1and 3. f

An' annularly moving wiping roller. I1 is adjusted towards the straight bar l5 and against an intervening flange iii of an angle bar, coextensive with bar 15, and welded or. otherwise secured to the bar; Both together, being stiif and rigid, are moved around over the face of table 2,

sliding thereon, by annular movement of the roller, as indicated in dotted lines in Fig. l. I

For such purpose a swinging supporting frame or bracket l9 iscarried by journalled bearings around post3, supported upon bearing 6 andhaY- ing an'operatlng lever arm2l extendingbey'ond a terminal head 22. A supplemental guide bar 23 connects head 22 byits inner pivoting terminal '24 rotatably around the upper end of afshort shaft or stud 25 whichwith bolts 1, fixedly connects the wheel 8 and table 2 with the upper end of post 3. Between head 22 and roller ll'is an adjusting housing 25, slidably mounted underneath the straight connecting guide bar 23 by embracing sides 21, and'having a depending supporting stud 28 around which the wheel IT is rotatably mounted. Connecting head22'andflthe housing, rotatably engaging the head and having'a rotating collar 29; isa screw 30in threaded engagement with the: housing; as in Fig. 2'."By

such means the housing and roller may be adjusted 'into operative relation'with the bar 15,

whereby to hold it and the blank A in continuous close working relation with the die Wheel-B, when lever arm! I is swung around, as indicated by the arrow, Fig. 1. I 1 7 Thus, as the roller 11 after, being accurately adjusted inwardly by. the screw to snugly embrace thev blank by straight groove E6 of bar 15, and

with opposite edge placementof the blank in shallow groove 9 of wheel 8, and ,with the end of its reversal, the swinging frame may then be re; I

turned for the next operation, the resultingarticle is removed, and the operation repeated.

Such removal is effected by releasing the-grip of bolt I3, retraction of housing 26 along its guide bar 23 with roller l1, removal of bar [5, resulting loosening of the thin Wall blank A outwardly The construction and operation of the ma-' chine will be readily understood and appreciated by those skilled in the art of bending pipes, tubing, etc. It efiectively, rapidly and successfully bends such, especially of small gauge walls, without buckling or wrinkles, due to the non-frictional application of rolling pressure through the means employed, while successively and continuously advancing the pressure zone during closely confining embracement of the pipe-inprocess.

The machine may be changed or varied in construction, dimensions or details, by the skilled from shallow groove 9, assisted'by its tendency to slight radial resilience outwardly, whereby the formed blank may be lifted away from. die wheelf; with limitedoutward swinging, if necessary. The machine as designed and used, is particularly adapted for operation on relatively thin wail blanks andrequires internal mandrel resistance, as indicated in Figs; 6 and 7. Such resistance is afforded by means of an entire filling of a suitable flexible and later removable substance was in Fig. 6, for in combination with a flexible core b, as'inFig: 7. g f,

The ratio of contraction of the mandrel being less than'that ofthe surrounding shell of the tube, results in a very intimate resisting contact, so that, due to the higher ratio contraction of the tube walls themselves, there results a very closely contacting and perhaps slight further compressing action on the mandrel.

The tube then being subjected to the action of the annular forming and rolling action of the machine elements, and due to the internal man- "drel resistance, .the'tube and its mandrel are laid or'wiped around the stationary disk wheel. Such treatment is without any frictional action such asresults in usual die forming bending, the operation contining until the complete resulting ring isformed, with the intervening gap.

Thereafter, the tube with its contained mandrel, is subjected to suflicient temperature, as by '"hot water immersion, sufiicient to melt the mandrel, which then freely flows outwardly from the shaped blank and is re-c'laimed for further use.

By reason of the adiustability of the roller the machine is well adapted to'p'erfect bending operations, notwithstanding slight variations in 'outer dimensions of the blank, more or less, from any standardsizes being operated on.

While there is an advantage in reinforcing the bar [5 by the co-extensive angle bar, with its flange I8 between the roller l1 and said bar, the bar l5'may-be made sufficiently strong and rigid itself, so that'the roller may bear directly against it, as in the modification shown in Fig. 8.

'It will also be understood that for bending other than almost completely circular or ringlike forms, thedie wheel or disk 8 may be replaced by segments thereof of any varying annularlength, curvature or radius, for curved bending thereover, merelyby reorganizing the design of the machine conformably.

Also, that instead of manual swinging of the frame l9, it may be power actuated, as by incorporating suitable gearing with the swinging frame, as an annular rack orgear wheel coin ciding with theaxial center of -post'3.-

mechanic to adapt it to any particular or special resulting product, within the scope ofthe following claims.

I claim:

1. A bending'machine for pipe or tubing comprising a table having an upper annular face stationary die member provided with a peripheral groove, a freely movable straight bar having a blank-engaging channel registering with said peripheral' groove, a wiping roller operatively r 2. A bending machine for pipe related to said bar, an annularly movable frame pivotally mounted below the table having an outer portion extending upwardly above the table, and adjusting and guiding means on the upwardly extending outer portion of said frame for maintaining the roller in operative relation tothe bar.

or tubing comprising a tablehavingan upper annular face stationary die member provided with a peripheral groove, a freely movable straight bar having a blank-engaging channel registering with said peripheral groove, a wiping roller operatively related to said bar, an annularly movable frame pivotally mounted below the table having an outer portion extending upwardly above the table, and adjusting and guiding means on the upwardly extending outer portion of said frame 'foradjusting the roller to operative relation with the bar and holding it against the die member during movement of the frame.

3. A pipe bending machine consisting of a supporting column having a stationary table and 'die member thereon having an annular blank engaging groove, an annularly swinging frame mounted on the column having a terminal extending above the table, a straight rigid bar slidably mounted on the table having a blank engaging channel for movable co-operation with the die member and its groove, a roller movable with the swinging frame for exerting inward pressure against the bar and moving it and an interposed blank around the die member, guiding means connecting the roller and the terminal of the swinging frame, and inwardly and outwardly adjusting means for the roller between it and the swinging frame terminal.

4. In a pipe bending machine for making a substantially complete ring, the combination with a central supporting column having a terminal'extension, of a stationary table having a fixed die member thereon provided with an annular edge'porticn, a swinging frame below the table having an outer terminal portion extending above the table movable around the axial center of the column and its extension, means connecting a tubular blank to the die member, a straight rigid barslidably mounted on the table having a blank-engaging channel, a guide bar connecting the terminal portion of the swinging frame with the terminal extension, a radially movable housing engaging the guide bar and provided with a roller, and adjusting means for the housingand its roller carried by the terminal portion of the swinging frame.

5. In a pipe bending machine, the combination with a central supporting column having a terminal extension, of a stationary table having a fixed die member thereon provided with an annular edge portion, a swinging frame below the table having an outer terminal portion extending above the table movable around the axial center of the column and its extension, means connecting a tubular blank to the die member, a straight rigid bar slidably mounted on the table having a blank-engaging channel and adapted to be moved over along the working edge of the die member in confining engage ment with an interposed blank, a guide bar connecting the terminal portion of the swinging frame with the terminal extension, a radially movable housing engaging the guide barand provided with a roller, and adjusting means for the housing and its roller carried by the terminal portion of the swinging frame.

6. In a pipe bending machine, the combination with a central supporting column having a terminal extension, of a stationary table having a fixed die member thereon provided with an annular shallow grooved edge portion, a swinging frame below the table having an outer terminal portion extending above the table movable around the axial center of the column and its extension, means connecting a tubular blank to the die member, a straight rigid bar slidably mounted on the table having a blank-engaging channel, a guide bar connecting the terminal portion of the swinging frame with the terminal extension, a radially movable housing slidably engaging the guide bar and provided with a roller, and adjusting means for the housing and its roller consisting of a screw journalled in the terminal portion of the swinging, frame and in threaded connection with the housing. 7

' with a central supporting column having a ter- 7. In a pipe bending machine, the combination minal extension, of an upper table secured to the column, a circular die member fixedly mounted thereon having an annular groove, a straight rigid bar slidably mounted on the table having a blank-engaging channel co-operating with the die member, an annularly movable swinging frame journalled on the column below the table having an outer terminal portion extending beyond and abovethe table, a guide bar journalled on the terminal extension of the col umn and secured to the terminal portion of the frame, a housingv slidably engaging the guide bar provided with a pivoted roller for exerting continuous inward pressure against the bar as the frame is moved annularly, and adjusting means for the housing between it and the terminal extension of the swinging frame.

8. In a pipe bending. machine, the combination with a central supporting column having a terminal extension, of an upper table secured to the column, a circular die member fixedly mounted thereon having an annular groove, a

straight rigid bar slidably mounted on the table column and secured to theterminal portion of the frame, a housing slidably engaging the guide bar provided with a pivoted roller for exerting continuous inward pressure, against the bar as the frame is moved annularly, and an adjusting screw for the housing between it and the terminal extension of the swinging frame.

RUSSELL M. WEIMER. 

